hi, I recently purchased a gtx 1070 founders edition. my question is, can I plug a 6 pin pcie power cable to it if the card has 8 pin slot? what would potentially happen if I did such thing? I know there are 6 pin to 8 pin adapters or molex ones, but im just curious how would this end up? would the gpu work?
It's not guaranteed that the 6-pin adapter can handle enough current as the 8-pin one, so it's not a good idea to adapt such.
Using a converter can be doable in theory, as long as you know how much power the card is expected to draw over time and how much power the PSU can provide from the connectors you're converting from. If we went from
Tom's Hardware's review of the 1070 FE, the card pulls 150W on average, with about 100W coming from the 8-pin connector (it's annoying they used a 3D graph so it's hard to tell exactly where it's floating). Molex connectors can provide up to 11A at 12V, so two of them, in theory, is plenty enough with wiggle room to provide an 8-pin PCIe connector with power. But this also assumes that both the PSU manufacturer and the converter maker did their part in using the correct wire gauge, which cheaper PSUs and converters will likely not have the correct wire gauge.
Anyway, take this information how you will.